Leader-following formation control of multiple vision-based autonomous robotic fish

A framework for the deployment of multiple autonomous robotic fish to achieve leader-following formations with Bezier trajectory is presented. Each follower robot estimates the position and orientation angle of its leader with a fast color-tracking vision system, and establishes a Bezier trajectory between its current position and the position of its leader robot. Considering the nonholonomic properties of the robotic fish, the optimization of Bezier curve´s curvature to choose appropriate scale factor is conducted by combination of penalty function and one-dimensional search methods to perform a smooth and stable trajectory. The optimal trajectories are accurate enough to estimate the angular velocity of the follower robot, while a fuzzy controller is used to adjust its linear velocity. By the introduction of virtual leaders, formations of different shapes can be generated. Experimental results show the effectiveness of our approach.